Metal form clamping device



Dec. 21, 1937.

W. A. JENNINGS METAL FORM CLAMPING DEVICE Filed July 27, 1956 PatentedDec. 21, 193'? UNITED STATES PATENT OFFICE METAL FORM CLAMPING DEVICEApplication July 27, 1936, Serial No. 92,754

1 Claim. (Cl. 25-131) I mould forms may be readily, quickly and easilyclamped together with sufficient firmness to withstand the shocks andjars to which such structures are subjected in use, and particularlywhen the cement between the forms is tamped or agitated, and whichclamping devices may be readily,

quickly and easily detached when the forms are being removed from anished concrete structure.

Referring to the accompanying drawing, Figure 1 shows a perspective Viewof my improved clamping device.

Figure 2 shows a side elevation of one of my improved clamping devicesapplied to the flanges of a metal form and illustrated in clampedposition. The dotted line shows the position of the pin.

Figure 3 shows a transvers-e sectional view through portions of twoabutting metal forms and their flanges, and through my improved clampingdevice applied thereto, illustrating a form of the invention in whichthe clamping device is frictionally held in position by bending theadjacent portions of the flanges of the metal form.

Figure 4 shows a similar view illustrating a modification in which thejaws of the clamping device are retained in position by springing intoopenings in the flanges of the forms.

Figure 5 is a similar view illustrating another modification in whichthe clamping device is held in position on the iianges by bending theflange laterally to one side and employing the resiliency of the liangeto hold the clamp in place.

Figure 6 shows a similar View of another modification in which theclamping device is held in place by a projection on the resilient jaw ofthe clamping device being sprung into position below the looped portionof the flange oi the mould form.

Figure 7 shows a similar view of another modication in which both jawsof the clamping device are resilient, and in this view they are shownspread apart by the thickness of the over-lapped portions of the flange;and Y Figure 8 shows a view of the same form of the invention with theresilient jaws sprung to position engaging the lower edges of theoverlapped portions of the ange of the metal forms.

Referring to the accompanying drawing, the clamping device, as clearlyshown in Figure 1, comprises a body portion I0, with a handle por- 5tion II at one end and an extension I2 at the other end, to whichextension, there is fixed a pin I3. Between the handle portion II andthe extension I2 there are two jaws I4 and I5. In this figure the twoljaws are provided with extensions 10 I6 and I1 at their ends furthestfrom the body, the extensions projecting toward each other.

This entire clamping device is preferably formed of a single piece ofresilient metal and is preferably cast complete in one piece so that itis cheap to manufacture and does notneed any machine.

The metal forms which I employ in connection with my invention arecomposed of relatively fiat body portions I8 made of resilient sheetmetal 20 and provided with flanges I9 whichk extend from the edges ofthe body substantially at right angles, and their outer ends are foldedback upon the flanges at 20, the edges of the members 2B being spacedapart from the body I8. These flanges are provided with a series ofopenings 2| preferably equally spaced apart throughout their entirelengths, so that the clamping device may be placed on any part of theiiange.

In the form of the invention illustrated in Figures 1, 'l and 8, I applythe clamping device as follows: I first insert the pin I3 through thealigned openings 2| in two of the fianges of the metal form. I thengrasp the handle portion and turn it pivotally centered upon the pin I335 until the jaws I4 and I5 engage opposite sides of the two iianges, asshown in Figure '7 where they are seen to be slightly sprung apart. Ithen, preferably with a hammer, strike the handle and drive the jawstoward the bodies of the forms until the projections I6 and I'I havepassed below the lower edges of the flanges 20, whereupon the jawsspring toward each other and thereby yieldingly hold the clamping devicein position and to clamp the two adjacent mould forms firmly together.

In practice I have found that with my improvement the forms are heldtogether with sufiicient rigidity to withstand the tamping or agitationto which the concrete in the mould forms is ordinarily subjected.

When it is desired to dismantle the mould form the operator may, bygrasping the handle II or by using a lever to pry them outwardly,quickly and easily swing them to position with the jaws 55 beyond theends of the overlapped flanges, and then the handle may be movedlaterally, either by hand or with the use of a hammer, to withdraw thepin. Obviously, these operations of applying the clamping device, orremoving it, can be accomplished very quickly and easily by unskilledlabor. Y v

In the modied form illustrated in Figure 6 I have shown a projection 22on one of the jaws only, the other one being left smooth and. straightand parallel with the adjacent portion of the flange of the form. Withthis construction the operation of applying or removing the clampingdevice is the same as that hereinbefore described, except that only oneprojection 22 is employed to hook under the adjacent edge of theoverlapped portion of the ange.

In Figure 4 I have shown another modification in which the clamping jawsare somewhat shorter in length than that shown in Figure 7, andotherwise the same only the projections 23' and 24 thereon are sopositioned as to enter the adjacent openings 2l in the anges of themould forms.

In the modication shown in Figure 5 I have shown one of the jaws 25 tobe of the same length as the adjacent overlapped portion 2i] of the angei9, and the other jaw is provided with an extension 25 at its lower endto pass under the lower edge of th-e adjacent overlapping portion 2E) ofthe ange of the mould form. In this modification the clamp is held inposition both by the resiliency ci the flanges i9 which are bentlaterally when this mcdiled form of the device is applied, and by theextension 26 being moved to position under the shoulder formed by theadjacent overlapping member of the ange.

In the modified form illustrated in Figure 3 I have shown the inneradjacent surfaces of both jaws, and slightly curved, and one jaw 2lterminates at about the lower end of the overlapping portion of theflange, while the other jaw is longer and has a projection 23 that eX-tends toward the adjacent ange below the overlapping portion. In thisform of the invention the resiliency of the flanges themselves aid inholding the clamping device in position, and in this form of theinvention the part indicated as 28 constitutes an inwardly extendedprojection which functions somewhat similar to the projections I6 and l1of the form of the invention illustrated in Figure l.

In practical operation with any of the forms of my invention hereindescribed I can easily, readily and quickly insert the pin I3, drive thehandle toward the anges, turn the handle in the direction toward theflanges of the metal forms and then drive the body l 0 with a hammer,

or otherwise, to position for causing one of the projections on theinner face of the jaws to position below the overlapping edge of theange or into the pin openings 2l, and when this has been done theresiliency either of the jaws themselves or of the flanges securelyholds the clamps in position and the metal forms rigidly in engagementwith each other.

I claim as my invention:

A clamping device comprising a lever, a fulcrum pin extended laterallyfrom one end portion of the lever, and a pair of jaws formed integralwith the lever and of resilient material, the space between the ends ofthe jaws furthest from the lever being less than the space between theremainder of the jaws and whereby when the jaws are forced upon twoarticles to be clamped together and which are relatively thick at Vtheirouter edges and of less thickness at a point spaced from said outeredges, the jaws -will Tre forced apart during the time when the jaws aremoving over said relatively thick portions and then spring toward eachother and form a frictional locking engagement with said articles whenthe end portions of the jaws reach said less thick portions of thearticles.

WILLIAM ALLEN JENNINGS.

